Role of bronchoalveolar lavage in diagnosing pulmonary infections and malignancies: Experience from a tertiary care center

Bronchoalveolar Lavage in Diagnostic Evaluation of Pulmonary Diseases- An Institutional Experience

Background

Bronchoalveolar lavage (BAL) is a widely accepted investigative tool for the diagnosis of pulmonary lesions. This study was done to find out the usefulness of BAL in diagnosis of pulmonary lesions from central Indian patient population.

Methods

A cross-sectional prospective study was performed over a period of three years. All the BAL specimens of patients presenting to Department of Pulmonary Medicine and Tuberculosis during a period of January 2017 to December 2019 were included in the study. Cyto-histopathologic correlation was done, wherever available.

Results

Of total 277 cases, there were 178 (64.5%) males and 99 (35.5%) females. The age of patients ranged from 4 years to 82 years. In 92 (33%) cases, specific infective etiology could be identified on BAL cytology, the most common being tuberculosis (26%) followed by fungal infections (2%). Rarely, infections like nocardia, actinomycosis, and hydatidosis were also identified. Eight cases (3%) of malignancy were identified which included two cases of adenocarcinoma, one case of small cell carcinoma, three cases of poorly differentiated carcinoma, and two cases suspicious for malignancy. Some rare diagnoses like diffuse alveolar damage, pulmonary alveolar microlithiasis, and pulmonary alveolar proteinosis could be identified on BAL.

Conclusion

BAL is useful in primary diagnosis of infections and malignancies of lower respiratory tract. BAL may aid in diagnostic workup of diffuse lung diseases. A combination of clinical information, high-resolution computed tomography, and BAL analysis may furnish an assured diagnosis to the clinician and obviate need for invasive procedures.

Integrated approach to bronchoalveolar lavage cytology to distinguish interstitial lung diseases

BACKGROUND

Broncho-alveolar lavage (BAL) is a safe diagnostic procedure, useful for differentiating fibrotic lung disorders and for excluding malignancy and infection. A recent multicenter study demonstrated a new, relatively sensitive, and specific index called Bronchoalveolar Cytology Threshold (BCT), useful for distinguishing healthy individuals from patients with lung diseases.

OBJECTIVES

In our study, BCT was applied for the first time to the analysis of interstitial lung diseases (ILDs), investigating its potential for differential diagnosis. Combinations of BAL cells that improve diagnostic accuracy for ILDs were studied and are proposed.

METHODS

A retrospective analysis of BAL samples was performed. We considered more than 1000 BAL samples from patients investigated for ILD, performed at Siena University Hospital. The samples enrolled for the study included 468 patients: 413 with and 55 without ILD. BAL was performed for diagnostic purposes in line with international guidelines. BCT were calculated according to available literature.

RESULTS

Among ILDs, patients with fibrotic hypersensitivity pneumonitis, idiopathic pulmonary fibrosis (IPF) and sarcoidosis showed significantly lower BCTs than unclassified ILD. Asbestosis patients showed significantly lower BCTs than nonspecific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia (COP), connective tissue disease related ILD (CTD-ILD), sarcoidosis and unclassified ILD patients. COP patients showed significantly higher BCT than IPF, f-HP and sarcoidosis. Moreover, COP patients were best distinguished by BCT.

CONCLUSION

The analysis of BAL features is currently included in the diagnostic algorithm of ILDs. BAL cell patterns and BCT index can provide useful information for distinguishing ILDs, reducing the need for invasive procedures. Integrated approaches to BAL analysis can improve the interpretation of results without further cost or loss of time.